What was found
DURING FLIGHT AT FL 370 ALL COCKPIT WINDSHIELDS FROSTED OVER, STARTED DESCENT. BOTH PRIMARY AIRSPEEDS SLOWED TO UNDER 200 KTS, STDBY READ NEAR RED LINE. FOUND WATER IN NR 2 PITOT LINE, CLEANED LINES IAW AMM 34-13-00, ADC 1 & 2 OPERATIONS CHECKED GOOD IAW AMM 34-15-00 ADC 1 & 2 LEAK CHECKED GOOD IAW AMM 34-13-00, NO LEAKS NOTED. ACFT WAS STILL PRESSURIZED UPON LANDING. DELTA P WAS ABOVE 1.2. PRESSURIZATION OPERATIONS CHECKED GOOD IAW AMM CH 21-31-00, NO DEFECTS NOTED. IAW ITEM NR 1 THIS AML PAGE. PITOT STATIC LINES NEED TO BE CHECKED FOR WATER. PERFORMED PITOT STATIC SYS SERVICING IAW AMM 31-13-00. NO WATER FOUND. REQUIRES FURTHER TROUBLESHOOTING.